Parade's End's success may have been bittersweet for Piers Wenger, the former BBC executive who worked closely with Sir Tom Stoppard to bring Ford Madox Ford's novels to the screen. By the time the acclaimed period drama aired on BBC2, Wenger had switched sides to Channel 4, where he is four months into his new role as head of drama.

"That was the show that in many ways was the hardest to leave," says Wenger. "I left about halfway through the shoot. I thought it was wonderful." Wenger will have to watch from another table at awards time if the adaptation cleans up, as expected. "I thought Benedict [Cumberbatch] and Rebecca [Hall] really worked in those roles. They found romantic comedy in a very unlikely place."

Now Wenger has his own parade to boast about, a trio of new dramas including New World, a sequel to the well-received civil war drama The Devil's Whore, written by Peter Flannery and Martine Brant. Home Before Dark, written by Abi Morgan (The Hour, The Iron Lady) with Kevin Macdonald as executive producer, is a four-part thriller spanning the UK, Italy and the US that examines the corrupting power of the internet. Another new commission, Dates, is a series of half-hour dramas by the Skins creator, Bryan Elsley, looking at modern relationships.

Apart from the award-winning pair of Ronan Bennett's Top Boy and Shane Meadows's This Is England '88, homegrown C4 drama has been relatively quiet of late, Wenger acknowledges. "There has been a pause but by the time the next few months are through it won't feel quite the same," he says .

His predecessor, Camilla Campbell, quit in December to set up her own production company, one of a string of executives to leave the broadcaster last year. "It wasn't like the shop was shut up – shows were commissioned after Camilla left and before I arrived," Wenger points out. "But since I've come into the post we have commissioned a lot of new stuff and next year will feel very rich and diverse."

But it is telling that the shows that come up in a discussion of the channel's recent hits, The Devil's Whore and David Peace adaptation Red Riding, were shown in 2008 and 2009 respectively. "They have that double helix of delivering great reputation for the channel but also being able to deliver the numbers," says Wenger. "That is the thing we are looking to do with the shows we commission."

Wenger joined C4 in 2011 at its big screen arm, Film 4, and will continue to oversee the projects he started there, including the keenly awaited Paul Raymond biopic King of Clubs, starring Steve Coogan. Previously head of drama at BBC Wales, Wenger executive-produced two series of Doctor Who and was responsible, along with its showrunner Steven Moffat, for the Doctor's latest incarnation in the shape of Matt Smith.

Moffat describes Wenger as "incredibly brilliant and sharp", and a very effective manager of creative talent. "He makes you feel clever all the time when it's actually probably him," says Moffat. "You go out with a flattering sense of your own brilliance when in fact what you are doing is what he wanted you to do in the first place."

Wenger lists Doctor Who and his two collaborations with Victoria Wood, Housewife, 49 (which Wood also wrote) and the Morecambe and Wise biopic Eric and Ernie, both of which won Baftas, as the shows of which he is most proud. He was also responsible for the misfiring Upstairs Downstairs comeback.

He met Wood after writing her a fan letter while he was still at ITV, where he began as a trainee script editor in 2000 working on the ill-fated soap Night and Day. "To my great amazement she replied," he remembers.

"I was a massive fan to an almost embarrassing degree. I could quote big swaths of her sketch shows," adds Wenger, who hopes the pair will collaborate again. "She understands characters' emotions and lives in a way that no one else does. She has a very thin skin which allows her to absorb and have insights into other people's emotional lives that audiences find a ring of truth around." Wenger began his career as a journalist on Just 17, but in his late 20s he took nine months out of journalism after his father was paralysed in a serious car accident. "I found myself watching lots of television drama and the depths and intellectual challenge of working in drama started to appeal."

He found out about his latest job when C4's chief creative officer, Jay Hunt, telephoned him in Los Angeles where he was celebrating his 40th birthday. She told him to talk to Tessa Ross, C4's controller of film and drama, when he returned, and he drove straight to Ross's house from the airport.

Wenger wants the next year of drama output on C4 to be a "shop window" for the range of work that writers and directors can expect to do on the channel. It will also include The Fear, starring Peter Mullan as a crime boss suffering from dementia, Dennis Kelly's cult conspiracy thriller Utopia, and Tony Grisoni's Southcliffe, about a fictional English market town devastated by a shooting spree.

"I want the buzzwords for next year to be scale and range," Wenger says. "I wanted to send a very clear message to the world that this is the place where you don't have to feel hidebound by a very defined commissioning brief.

"There is a huge amount of drama which is of a certain type, the trick to get audiences to come to them afresh is to find new ways into those stories, new perspectives on these subject matters and the only way to do that is to empower the authors."

C4's hit US series Homeland, a Showtime adaptation of the Israeli drama Hatufim, returns for its second season next month. Wenger says the channel can take inspiration from the show, which finished its first run with an overnight audience of nearly 3 million.

"We don't want to be a minority choice. I've always worked on really mainstream shows, whether it's Doctor Who or my work with Victoria Wood. My instincts are to try and reach as big an audience as possible," he says. "If you look at the success of Homeland, or even the Paralympics, Channel 4 is a place where you can take a big idea and shape it in a unique way."

Like Homeland, Abi Morgan's thriller Home Before Dark will be given a 9pm slot. "We are going to attack 9 o'clock hard. We absolutely want to compete on as big a stage as possible."

Paul Abbott's Shameless has been a ratings banker since 2004. But after 115 episodes and in the middle of series 10 (an 11th is already in the pipeline), how long can it and Frank Gallagher last? "It's like every series, we look at how they perform when they go out, and how the creative team feel about how much more they have to say," says Wenger.

More serious questions have been asked of Hollyoaks, as this year Hunt said the 17-year-old tea-time soap was "not on its best form". "It had a tough summer but like any soap its ratings can go up and down," says Wenger. Is it on notice? "Absolutely not. The sense was we needed to look at it and make it stronger, and we've done that." Its producer, Bryan Kirkwood, credited with reviving the show between 2006 and 2009, has returned after a stint on EastEnders, and last week it had around 1 million viewers, a 5%-6% share. "It has to reflect the audience's life in an entertaining and authentic way," says Wenger.

As he looks for C4's next big hit, thoughts turn back to Parade's End. "Even though it was quite a lengthy and exhausting process getting that show financed and co-produced and cast, I am really glad that it has found an audience and that what was there in the novels has resonated with people thanks to Tom," says Wenger.

"There are [other] literary properties that feel as difficult and as brilliant as those novels did that we are going after, because I think that's the best of what television can offer people."